The addition of topographic information to the ALTA survey is optional Table A Item 5. If requested, the surveyor will report the contours of the land in one-foot intervals. It is often used by architects or site development engineers. Adding the topographic element can add significant cost to the survey but it is valuable information, particularly in development, used to answer questions about site drainage or drainage easements.
For more information about ALTA with Topographic Surveys, please review Item 5 in Section 3 of the Bock & Clark Handbook for ALTA/NSPS Land Title Surveys.